MDEV-9350 Fix jemalloc detection for FreeBSD

on FreeBSD 10 jemalloc is in libc, no separate libjemalloc is needed

Author: vuvova

cmake/jemalloc.cmake

@@ -20,18 +20,22 @@ MACRO (CHECK_JEMALLOC)
  SET(CMAKE_REQUIRED_LIBRARIES pthread dl m)
  SET(what bundled)
  ELSE()
- SET(libname jemalloc)
+ SET(libname jemalloc c)
  SET(what system)
  ENDIF()
 
- CHECK_LIBRARY_EXISTS(${libname} malloc_stats_print "" HAVE_JEMALLOC)
+ FOREACH(lib ${libname})
+ CHECK_LIBRARY_EXISTS(${lib} malloc_stats_print "" HAVE_JEMALLOC_IN_${lib})
+ IF (HAVE_JEMALLOC_IN_${lib})
+ SET(LIBJEMALLOC ${lib})
+ SET(MALLOC_LIBRARY "${what} jemalloc")
+ BREAK()
+ ENDIF()
+ ENDFOREACH()
  SET(CMAKE_REQUIRED_LIBRARIES)
 
- IF (HAVE_JEMALLOC)
- SET(LIBJEMALLOC ${libname})
- SET(MALLOC_LIBRARY "${what} jemalloc")
- ELSEIF (NOT WITH_JEMALLOC STREQUAL "auto")
- MESSAGE(FATAL_ERROR "${libname} is not found")
+ IF (NOT LIBJEMALLOC AND NOT WITH_JEMALLOC STREQUAL "auto")
+ MESSAGE(FATAL_ERROR "jemalloc is not found")
  ENDIF()
  ENDIF()
 ENDMACRO()